Natasha, who is only the size of a toddler, is thought to have never left the squalid, unheated three-room flat she lived in with her dad and grandparents.

Rescuers found her dressed in ripped and soiled clothes and surrounded by dogs and cats following a tip-off from concerned neighbours on Monday.

Police said: "For five years the girl was brought up by several dogs and cats and had never been out."

One neighbour in the city of Chita, Siberia, said: "We didn't know she existed. They have three vicious dogs they took for walks but we never saw this child."

Natasha, nicknamed Mowgli after the Jungle Book character raised by animals, is now at a rehabilitation centre where specialists are shocked at the way she leaps at humans and plays dog games.They say she is not mentally retarded, just starved of contact with humans - and shuns other children.